ok, so I recently got this 1991 SL300 that has a few electrical issues that I will list below... I did, by the way, replace each and every single fuse in both front and rear panels... that made my windows work again, then the windows blew both 8A fuses in the rear box again for some reason, I replaced them and they've been working since... other fuses are still ok since replacement...

Now, my main issue is that the instrument cluster is only working partially, all gauges (speedometer, tach, fuel, etc) are inoperational - with the exception of engine temp and all warning lights seem to work OK too... I read around, and it doesn't seem to be the dreaded intermittent cluster issue related to some resistor in the cluster itself... however, I've read about some other people having a similar issue to mine due to a "bad" switch, or "bad" light - so my (1) question is how do I test for a "bad" switch or light with a multimeter, and are there any particular circuits I should concentrate on???

also, some power options dont work, such as the power hardtop release... when I push the switch nothing happens (it does blink red though)... I am guessing there must be a relay somwhere - so my other question (2) is where is that relay and can I test it???

the seats lost power, but I was told by previous owner that the switches tested out OK and the seats move if power is jumped to them with a wire... so, another question (3) is there a relay for the power seat adjustments?

is there a place anywhere to download a wiring diagram for my car (or similar)???

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1991 MB SL300, 1994 Sub 4x4 6.5L TD, 1986 K30 4x4 6.2L, other toys
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"Back up four feet and floor it..."